VULNERABILITY INTELLIGENCE

CVE-2021-3418

CVSS score6.4 MEDIUM
EPSS probability0.47%
CISA KEVNot currently listed
Published2021-03-15
Last modified2026-06-17
CVSS vectorCVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H

Description

If certificates that signed grub are installed into db, grub can be booted directly. It will then boot any kernel without signature validation. The booted kernel will think it was booted in secureboot mode and will implement lockdown, yet it could have been tampered. This flaw is a reintroduction of CVE-2020-15705 and only affects grub2 versions prior to 2.06 and upstream and distributions using the shim_lock mechanism.

Weakness classification

  • CWE-281: Improper Preservation of Permissions

Primary references